---
title: GoodThopter12
---
<h1>GoodThopter12</h1>

<p>The GoodThopter12 is a sexy GoodFET CAN device based around the
design of the <a href="/hardware/goodfet31/">GoodFET31</a>. Unlike the
general- purpose GoodFET boards, the purpose of this board is to be
used in the exploration of Automotive communication buses, currently
supporting only the CAN bus. In addition to GF31 circuitry we have
added a high-speed CAN Transceiver (MCP2551) and a Stand-alone CAN
Controller with a SPI Interface (MCP2515).  This design improves upon
the <a href="/hardware/goodthopter10/">GoodThopter10</a> by correcting
one important and many minor errata and improves on the GoodThopter11
by allowing users to purchase the cheaper OBD2 cables from SparkFun
or OBD2Cables.com.
</p>


<p><a href="http://www.flickr.com/photos/travisgoodspeed/7799398280/" title="GoodThopter10 by Travis Goodspeed, on Flickr"><img src="http://farm9.staticflickr.com/8289/7799398280_d1093d3ce5.jpg" width="500" height="282" alt="GoodThopter10"></a></p>

<h2>CAD Files</h2>

<p>Eagle CAD 6.x files for the design can be found in
/branches/goodthopter12 of the GoodFET subversion repository, or along
with gerbers as
<a href="/releases/goodthopter12.zip">goodthopter12.zip</a>.</p>

<h2>Bill of Materials</h2>

<p>Resistor values can be approximated.</p>

<p><b>N.B., The BOM including Digi-Key part numbers can be found in SVN branches/goodthopter10/bom/ (GoodThopter10 uses the same components)</b></p>

<p><table border="1">
<tr><td>Quantity</td><td>Package</td><td></td></tr>
<tr><td>1</td><td>SSOP28</td><td><a href="http://www.ftdichip.com/Products/FT232R.htm">FT232RL</a></td></tr>
<tr><td>1</td><td>TSSOP38</td><td><a href="http://www.ti.com/product/msp430f2274">MSP430F2274</a></td></tr>
<tr><td>1</td><td>TSSOP20</td><td><a href="http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en010406">MCP2515</a></td></tr>
<tr><td>1</td><td>SOIC8</td><td><a href="http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en010405">MCP2551</a></td></tr>
<tr><td>1</td><td>HC49/UP**</td><td>20MHz SMD Crystal, 15pF</td></tr>
<tr><td>4</td><td>0603</td><td>0.1&mu;F Decoupling Capacitors</td></tr>
<tr><td>2</td><td>0603</td><td>15pF Capacitors*</td></tr>
<tr><td>5</td><td>0603</td><td>0603 LED</td></tr>
<tr><td>4</td><td>0603</td><td>330R LED Series Resistors</td></tr>
<tr><td>1</td><td>0603</td><td>10K Pull-up Resistor</td></tr>
<tr><td>2</td><td>0603</td><td>0 OHM Resistors - Jumpers for OBD2 Cable</td></tr>
<tr><td>1</td><td></td><td>USB Type B - TE 292304-2 or FCI 61729-1011BLF</td></tr>
<tr><td>1</td><td></td><td>D-SUB 9 Position Mountable Conn. - TE 1734351-1</td></tr>
</table>
</p>

<p>* These should match the required capacitance of the crystal.</p>
<p>** The /US SMD package works as an alternative.</p>

<h2>Construction</h2>

<p>Place the components as shown in the comments of this Flickr image.
As this is a surface-mount design, be sure that you are familiar with
such techniques or have assistance before beginning assembly.</p>

<a href="http://www.flickr.com/photos/travisgoodspeed/7799398280/" title="GoodThopter10 on Flickr"><img src="http://farm9.staticflickr.com/8289/7799398280_d1093d3ce5.jpg" width="500" height="282" alt="GoodThopter10"></a>

<p>See the <a href="http://goodfet.sourceforge.net/tutorial/">GoodFET
Tutorial</a> for more detailed explanations.</p>

<h2>Usage</h2>

<p>Build and flash firmware with the following commands.  This board
self-flashes over USB through a masked-ROM bootloader, so there is no
need for an external programmer.</p>

<p><pre>export board=goodthopter12
make clean install
goodfet.mcpcan info
</pre></p>

<p>See the <a href="http://goodfet.sourceforge.net/tutorial/">GoodFET
Tutorial</a> for more detailed explanations.</p>

<h2>OBD2 Cables</h2>

<p>NEW! On the GoodThopter12 you have your choice of OBD2 cable. We suggest
purchasing the much cheaper <a href="https://www.sparkfun.com/products/10087">Sparkfun model</a></p>
<p><b>Note: the SparkFun cable does not work with previous versions of the GoodThopter (10,11)</b></p>

<a href="http://www.flickr.com/photos/andrewrighter/8629206120/" title="GoodThopter12 Cable Selection">
<img src="http://farm9.staticflickr.com/8534/8629206120_32090373c6.jpg" width="324" height="500" alt="GoodThopter12 - Cable Selection"></a>
<p>
Looking at the image above, this is the GoodThopter12 silkscreen.  We
routed the SparkFun OBD2 cable by default, so if you use this cable
you don't need to do anything.</p>

<p><b>IMPORTANT!</b> For those who have previous GoodThopter devices
and wish to use their existing cable (the one from ICS) then you can
do so by populating resistors R6 and R8 AND cutting the traces to the
SparkFun lines (see silkscreen). We hope this alleviates the expensive
purchase of the ICS cable and allows all future users to purchase
SparkFun's cable for much less!
</p> 
